Adding PYTHONPYCACHEPREFIX / PyCachePrefix option.

Author: ppisl

CHANGELOG.md

@@ -4,8 +4,10 @@ This changelog summarizes major changes between GraalVM versions of the Python
 language runtime. The main focus is on user-observable behavior of the engine.
 
 ## Version 20.1.1
-* When a `*.py` file is imported, `*.pyc` file is created. It contains binary data to speed up parsing. 
-   
+* When a `*.py` file is imported, `*.pyc` file is created. It contains binary data to speed up parsing.
+* Adding option `PyCachePrefix`, which is equivalent to PYTHONPYCACHEPREFIX environment variable. 
+* Adding optin `DontWriteBytecodeFlag`. Equivalent to the Python -B flag. Don't write bytecode files.
+* Command option -B works
 
 ## Version 20.1.0
 

graalpython/com.oracle.graal.python.shell/src/com/oracle/graal/python/shell/GraalPythonMain.java

@@ -377,6 +377,10 @@ protected void launch(Builder contextBuilder) {
             verboseFlag = verboseFlag || System.getenv("PYTHONVERBOSE") != null;
             unbufferedIO = unbufferedIO || System.getenv("PYTHONUNBUFFERED") != null;
             dontWriteBytecode = dontWriteBytecode || System.getenv("PYTHONDONTWRITEBYTECODE") != null;
+            String cachePrefix = System.getenv("PYTHONPYCACHEPREFIX");
+            if (cachePrefix != null) {
+                contextBuilder.option("python.PyCachePrefix", cachePrefix);
+            }
         }
 
         String executable = getContextOptionIfSetViaCommandLine("python.Executable");
@@ -552,8 +556,7 @@ protected String getLanguageId() {
     protected void printHelp(OptionCategory maxCategory) {
         print("usage: python [option] ... (-c cmd | file) [arg] ...\n" +
                         "Options and arguments (and corresponding environment variables):\n" +
-                        "-B     : on CPython, this disables writing .py[co] files on import;\n" +
-                        "         GraalPython does not use bytecode, and thus this flag has no effect\n" +
+                        "-B     : this disables writing .py[co] files on import\n" +
                         "-c cmd : program passed in as string (terminates option list)\n" +
                         // "-d : debug output from parser; also PYTHONDEBUG=x\n" +
                         "-E     : ignore PYTHON* environment variables (such as PYTHONPATH)\n" +

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/SysModuleBuiltins.java

@@ -192,6 +192,8 @@ public void postInitialize(PythonCore core) {
             sys.setAttribute("_base_executable", context.getOption(PythonOptions.Executable));
         }
         sys.setAttribute("dont_write_bytecode", context.getOption(PythonOptions.DontWriteBytecodeFlag));
+        String pycachePrefix = context.getOption(PythonOptions.PyCachePrefix);
+        sys.setAttribute("pycache_prefix", pycachePrefix.isEmpty() ? PNone.NONE : pycachePrefix);
         sys.setAttribute("__flags__", core.factory().createTuple(new Object[]{
                         false, // bytes_warning
                         !context.getOption(PythonOptions.PythonOptimizeFlag), // debug

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PythonOptions.java

@@ -105,6 +105,9 @@ private PythonOptions() {
     @Option(category = OptionCategory.USER, help = "Equivalent to the Python -B flag. Don't write bytecode files.", stability = OptionStability.STABLE) //
     public static final OptionKey<Boolean> DontWriteBytecodeFlag = new OptionKey<>(false);
 
+    @Option(category = OptionCategory.USER, help = "If this is set, GraalPython will write .pyc files in a mirror directory tree at this path, instead of in __pycache__ directories within the source tree. Equivalent to setting the PYTHONPYCACHEPREFIX environment variable for the standard launcher.", stability = OptionStability.STABLE) //
+    public static final OptionKey<String> PyCachePrefix = new OptionKey<>("");
+
     @Option(category = OptionCategory.INTERNAL, help = "Set the location of C API home. Overrides any environment variables or Java options.", stability = OptionStability.STABLE) //
     public static final OptionKey<String> CAPI = new OptionKey<>("");
 

graalpython/lib-graalpython/sys.py

@@ -149,8 +149,6 @@ def make_hash_info_class():
 # continue prompt for interactive shell
 ps2 = "... "
 
-pycache_prefix = None
-
 # Stub audit hooks implementation for PEP 578
 def audit(str, *args):
     pass